# Zetamac Arithmetic Practice vs 21 Sharp

The clearest difference is in-app purchases: Zetamac Arithmetic Practice at none against 21 Sharp's 1. Zetamac Arithmetic Practice also leads on ratings volume (18 vs 1). 21 Sharp's advantage is rating (5.0 vs 4.7). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. 21 Sharp sells 1 one-off in-app purchase. Zetamac Arithmetic Practice asks for nothing beyond the download.

21 Sharp holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Zetamac Arithmetic Practice has 18 ratings behind it against 1, so its average is the more settled of the two.

## The numbers

| Metric | Zetamac Arithmetic Practice | 21 Sharp |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.7 (18 ratings)](https://appshunter.io/ios/app/zetamac-arithmetic-practice/id6737153617/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/21-sharp/id6757319502/reviews)** |
| Number of ratings | **18** | 1 |
| Positive reviews | 83.3% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Daily | — |
| Monetization | **Free** | Free with in-app purchases |
| Size | 1 MB | 1 MB |
| Requires iOS | 17.5 | **17.0** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 12+ |
| Developer | [Joseph Ma](https://appshunter.io/developer/1774979062) | [busyslacker llc](https://appshunter.io/developer/1576079901) |

## What reviewers say

### Zetamac Arithmetic Practice

[App page](https://appshunter.io/ios/app/zetamac-arithmetic-practice/id6737153617)

This app offers mental math practice tailored for quantitative finance professionals. It focuses on improving calculation speed and accuracy for complex numerical problems.

**Highlights:** Mental math practice, Quantitative finance focus, Calculation speed improvement, Accuracy enhancement, Numerical problem solving

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### 21 Sharp

[App page](https://appshunter.io/ios/app/21-sharp/id6757319502)

Master blackjack strategy and card counting with this professional-grade trainer. Learn optimal plays, practice counting systems, and track your progress with realistic simulations and reference guides. Reduce the house edge and gain a competitive advantage.

**Highlights:** Basic strategy training, Card counting drills (Hi-Lo), Realistic practice table, Reference guides, Progress tracking and achievements

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 21 Sharp Premium | $2.99 | one-time |


## Frequently asked questions

### Is Zetamac Arithmetic Practice free?

Zetamac Arithmetic Practice is free to download, with no in-app purchases.

### Is 21 Sharp free?

21 Sharp is free to download, with in-app purchases available.

### Which has better reviews, Zetamac Arithmetic Practice or 21 Sharp?

21 Sharp is rated higher. Zetamac Arithmetic Practice averages 4.7 out of 5 from 18 ratings, while 21 Sharp averages 5.0 from 1 ratings.

### Do Zetamac Arithmetic Practice or 21 Sharp have ads?

Neither Zetamac Arithmetic Practice nor 21 Sharp shows ads.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*